New Transforms for Image and Video Compression

Encoding data includes: computing a first set of coefficients based on a plurality of transforms each computed over a different portion of an array of data, and a second set of coefficients based on a transform computed over the array of data; choosing a set of coefficients to represent the array of data from a group of multiple sets of coefficients, the group including the first set of coefficients and the second set of coefficients; and encoding the chosen coefficients and one or more parameters related to the chosen coefficients.